The study protocol included cognitive screening through the Korean version of the Mini-Mental State Examination (K-MMSE), which has been validated for the Korean-speaking population ({YW, 1997 #88}Kang YW et al., 1997), recording of the subject's medical history. A Korean study in the community defined the cut-off point of K-MMSE score during the screening of dementia as 17/18 points; the sensitivity and specificity of the findings were 91% and 86%, respectively ({YW, 1997 #88}Kim et al., 2003). Based on these results, we defined cognitive impairment (CI) as the group that had a K-MMSE score lower than 17, and not cognitive impairment (NCI) was defined as the group that had a K-MMSE score higher than 18.